212 Intelligence and Miscellaneous Articles. 



surfaces of feeble kathode rays may be doubled or bifurcated if the 

 rays are strengthened. This phenomenon may be compared with 

 the bifurcation of the interference surfaces of strong sound waves 

 which was demonstrated by E. Mach. 



The author contests the existence of Goldstein's deflexion as 

 being due to an action at a distance of the kathode elements on 

 the kathode rays. The phenomena of deflexion may be explained 

 partly by interference and partly by the electrostatic deflexion 

 of kathodic rays. 



Even before the discovery of the electrostatic deflexion of 

 kathode rays, it was inferred from the theory of the author that 

 simple feeble kathode rays follow the maxima and minima lines of 

 the electrostatic field, but are deflected from these lines by 

 magnetic force. This is calculated to explain all the deflexions of 

 the kathode rays hitherto known. Above all, this explains what 

 at first sight is the unexpected direction of the electrostatic 

 deflexion of the kathode rays, as well as the deflexion of the 

 starting-point on the kathode. The statement of E. Wiedemann 

 that in the electrostatic deflexion only the starting-point is 

 displaced, and that the rays continue rectilinear and perpendicular 

 to the kathode is experimentally refuted. 



The spontaneous stretching of the kathode rays is brought nearer 

 an explanation as being a simple phenomenon of discharge. This 

 incited experiments to compel the kathode rays to travel to the 

 anode. Anode rays were obtained, that is kathode rays which 

 proceed from the side of the glass, but do not remain perpen- 

 dicular, but curve to the anode, and collect in a thin stem. The 

 glass side scarcely fluoresces at all, but there is a bright fluorescent 

 spot on the corresponding prepared anode. These anode rays are 

 of the same nature as the kathode rays and show also corresponding 

 deflexions. — Wiener Berichte, July 1897. 



ON THE MEASUREMENT OF THE BRIGHTNESS OF DAYLIGHT. 

 BY H. W. VOGEL. 



The author gives the following as the results of a series of 

 observations on this subject by a method which be describes ; 

 they were made in Berlin in January of this year in very variable 

 weather, and show the enormous differences of daylight in winter. 



Jan. 13, 3 p.m. Strong fog .... 23 metre-candles 



„ 14,2 p.m. Slight fog 79-59 „ „ 



„ 15,2 p.m. Grey sky. Eog. . 89-55 

 „ 16, 2 p.m. Grey sky. Eog. . 55*54 „ „ 

 „ 22, Sunny day. Clear, some- 

 what misty .... 394-5 „ ,, 



Wiedemann's Annalen, June 1897. 



